This invention relates generally to devices connected to AC power lines, and more particularly to communication information between wireless telephone devices, Internet devices, and home appliances.
There is a great interest in communicating information with devices connected to AC power lines. More particularly, users would like to control and sense home appliances remotely. Currently, it is possible to transmit and receive computer, television, and telephone signals on AC power lines. In the future, users would also like to be able to monitor and control thermostats, refrigerators, stoves, lighting fixtures, heating and cooling systems, and the like, while away from their homes.
In such arrangements, one or more appliances, e.g., PCs, televisions, telephones, stereos, would be connected to the AC power line for receiving power, and a power line communication (PLC) adapter could be used for receiving and transmitting the information signals. The PLC adapter can be embedded in the appliances to extract information signals from the AC power line.
Most prior art literature describing power line communication networks has mainly been concerned with the physical layer specification of power line communication (PLC) protocols. For example, the art has focused on modulators, demodulators, converters, filters, signal detectors, synchronizers, and the like.
In addition, most prior art systems only permit communication between like devices, or communicating to a specific class of devices, for example, only between telephone, only between audio monitors, only to NTSC type devices, and so forth.
U.S. Pat. No. 5,777,545 xe2x80x9cRemote control apparatus for power line communications system,xe2x80x9d issued to Patel, et al. on Jul. 7, 1998, describes a remote control device for a power line communications system that uses pulse code modulation.
U.S. Pat. No. 5,805,053 xe2x80x9cAppliance adapted for power line communications,xe2x80x9d issued to Patel, et al on Sep. 8, 1998, describes electrical appliances receiving and transmitting information to each other over a power line. The arrangement uses a transformer, bandpass filter, and amplifier and shaper.
U.S. Pat. No. 6,084,758 xe2x80x9cPower distribution system with circuit breakers remotely resettable by signals transmitted over the power lines,xe2x80x9d issued to Clarey et al. on Jul. 4, 2000, describes a power distribution system where circuit breakers at a load center are remotely reset by reclosers using a power line communication system, such as an X10 or CEBus system. A remote master unit, which generates reset signals, is connected to an unaffected branch circuit, preferably by plugging into an accessible location remote from the affected load center. The reclosers may be addressed individually or globally by the master unit.
U.S. Pat. No. 6,218,931, xe2x80x9cHome-appliance network with nodes identified by direct-sequence spreading codes,xe2x80x9d issued to Asghar et al. on Apr. 17, 2001, describes a network interface that couples residential appliances into a code-division multiple access (CDMA) network to convey appliance control and status signals. A spreading-code generator generates the codes, and a spread mixer modulates a narrowband transmit signal with the spreading code that is then coupled into the physical medium of the network.
U.S. Pat. No. 6,246,868 xe2x80x9cConversion and distribution of incoming wireless telephone signals using the power line,xe2x80x9d issued to Bullock et al., on Jun. 12, 2001 describes a system where wireless signals are received, converted, and distributed over AC power lines to one or more telephone communication devices within a building, office or complex is disclosed. That system provides for the reception of PCS, cellular and/or satellite communication signals, and provides an interface to standard generally available telephone equipment. By making use of a power line carrier channel, telephone equipment located remote from standard telephone wiring can be accessed. Moreover, by distributing such received wireless signals over the power line a number of telephone devices can be used to receive the distributed signals. In addition, the system allows previously installed telephones to communicate over and with wireless communication devices. As a limitation, that system is only concerned with distributing telephony signals, and does not address the general problem of controlling and communicating with a variety of non-telephonic home appliances, and the problem of acquiring status information about the appliances.
U.S. Pat. No. 6,288,632 xe2x80x9cApparatus and method for power line communication (PLC),xe2x80x9d issued to Hoctor, et al. on Sep. 11, 2001, provides a transmitter that broadcasts a signal for communicating information over a power line. The signal includes a superset, and the superset includes tone sets. Specifically, the signals of the tone sets are characterized by a spectral shape exhibiting main lobes within a harmonic interval. There is a main lobe for each different tone set.
Recently, IBM has described a software toolkit called the Service Management Framework(trademark), which is designed to be fully compliant with the OSGI (Open Service Gateway Initiative). The OSGI specification is an open industry standard for connecting xe2x80x9csmart devicesxe2x80x9d to the Internet, including everything from home appliances and set-top boxes to game machines and medical devices. Thus, the connected devices can be operated remotely. Unfortunately, that tool kit does not address the general problem of devices that only have a connection with a power line.
Therefore, there is a need for a system, method and network that enables remote users to communicate with and to control a variety of devices whose only electrical connection is to a power line network.
A network enables remote users to communicate with, and to control a variety of devices whose only electrical connection is to a power line network. In hybrid networks, communication between different network domains is only available if proper message mapping is done. Message mapping leads to the determination of correct frame conversion based on the specifications of protocols identifying different networks. This invention comprises a method that does bi-directional conversion between application level information entered into the remote access device by the user and related physical layer power line communications frames.